Selling old house: Capital gains tax hack I found

After selling our big house, I've been looking for a compact 2BHK in Greater Noida for almost six months now. Ek cheez jo maine realize ki, especially for people like us who are selling an old property to buy new, Section 54EC bonds can save a lot on capital gains tax. Many don't talk about this. GDA flats ya Godrej Properties mein, is there any specific documentation ya process jo log miss karte hain for these benefits? Also, any tips for checking maintenance costs in Sector 150 societies? Hope this helps someone planning to sell and buy. Aur koi tax hacks hain toh please share.